Make Food-Safe Silicone Mould from Master Mould
In our previous post, we explained how to 3D print a master mould using your own printer. In this guide, we'll show you how to turn that master mould into a food-safe silicone mould for your chocolate creations.
Platinum-Cured Silicone
For food-grade applications, only platinum-cured silicone meets the required standards. While tin-cured silicone is more cost-effective, its tin compounds can leach into food, and animal studies suggest that ingested tin may harm internal organs.
Remember, NOT ALL platinum-cured silicone is inherently food safe—ensure that the product is clearly marked as food-safe by the manufacturer.
Also, be aware that platinum-cured silicone can experience cure inhibition when in contact with resin 3D prints. To prevent this, expose the resin print to UV light while it is submerged in water for 10 hours or more.
Materials and Tools
- Two-part platinum-cured silicone rubber (make sure it is food-safe)
- A plastic mixing cup
- A wooden stir stick
- A vacuum pump and a vacuum chamber (for degassing the silicone)
- Your 3D-printed master mould
Step-by-Step Process
1. Mixing the Silicone
Pour the two parts of the silicone into a plastic cup and stir them thoroughly with the wooden stick.
2. Degassing the Mixture
Place the cup with the mixed silicone into a vacuum chamber to remove any trapped air bubbles.
3. Pouring the Silicone into the Master mould
Carefully pour the silicone into your master mould, ensuring you fill the lower sections first to minimize bubble formation.
4. Secondary Degassing
Once poured, place the filled master mould back into the vacuum chamber for a second degassing to eliminate any remaining bubbles.
5. Curing and Demoulding
Allow the silicone to cure for several hours, following the manufacturer's instructions for the exact curing time. After the silicone has fully set, gently remove the food-safe mould from the master mould. You now have a custom mould ready for making chocolate!
Conclusion
Transforming your master mould into a food-safe silicone mould is a rewarding DIY project that adds a personal touch to your chocolate-making. By using platinum-cured silicone, you ensure that your mould is both durable and safe for food contact. Follow these steps—from mixing and degassing to pouring and curing—and soon you'll be enjoying beautifully crafted, custom-made chocolates.
Happy moulding and even happier chocolate making!
